One huge thing that I like about this forum is that everyone has their opinions and I haven't seen too many get upset. As a professional truck driver I'm going to give mine.
Feel free to search my profile for previous posts. I did my research myself and bought from the place I could get the best prices. I have recently posted about my use of the SuperHitch and SuperTruss setup.
As far as extending the tongue on a trailer. I believe it's unsafe. Hear me out...if you're a professional fabricator, then by all means I trust you. Most aren't. But anyone can bolt a few things together and wham you've got a well designed, quality product. You wouldn't make your Shortbed pickup into a Longbed pickup in your driveway. I hope my point is coming across.
A trailer is part of a frame that was designed, engineered, and tested to handle weight in a certain way. Altering a frame isn't a good idea.
People use hitch extensions everyday without problems. I have no doubt about the safely of a superhitch setup and the way it's mounted or assembled. People on here haul heavier things than me with longer extensions too, and have been doing it for longer than I've been in the game.
If you don't have a horse trailer now and plan on buying the right one to be able to tow it without an extension, I see no harm in that.
There are a lot of way opinions can go. Take things for what they are worth and if you've seen a thought you hadn't come up with yet, then we are doing our jobs. Sounds like you've got a pretty good understanding of how to achieve what you'd like to do.
Forgot to add, everyone seems to like the torklift stuff for any extension option. It's probably the safest option...especially if you're going to be hauling heavy, living things. Make sure that those short extensions you've mentioned are rated for hauling 5500lbs, preferably with some safety margin. I wouldn't imagine those things are solid 2" bar stock, and I'm sure when made they were thinking a dirt bike trailer or a small aluminum boat, or a bicycle rack. If you're going to be using a weight distributing system, that changes the game as well.
